We recently implemented the Document Conversion API from IBM Watson.In this can I use web files (www.something.com) as input.
curl -X POST -u "username":"password" -F config="{\"conversion_target\":\"answer_units\"}" -F "file=@www.something.com/readme.html;type=text/html" "https://gateway.watsonplatform.net/document-conversion/api/v1/convert_document?version=2015-12-15"